Based on the crane in service as application object, this paper presents crane running data detection software system based on VB6.0 serial communication technology. The sensors distributed on crane running motors are realtime monitored by the software. Current and voltage signal can be acquired through the wireless serial communication, realizing test data acquisition and the background analysis function. The test results indicate that the software can obtain accurately the running data of crane motors, and realtime display dynamic curve, providing a convenient and high efficient method of data collection technology for crane testing.